Total Knee Replacement (TKR)

The knee joint is a hinge joint, formed by thigh bone (femur) and the shin bone (tibia). Usually the surfaces of the bones are covered with a smooth coating (articular cartilage). When this coating wears away in arthritis, the joint surfaces become rough, causing pain and stiffness.

A total knee joint replacement operation removes the damaged surfaces and replaces them with metal and plastic parts. In return, it will help to:

• decrease pain
• decrease stiffness
• improve your ability to get around, including stairs, and some recreational activities

Traditional total knee replacement involves a 7-8” incision over the knee, a hospital stay of 3-5 days, and a recovery period typically lasting from one to three months. Studies showed excellent results in most cases of TKR, with substantial or complete relief of the arthritic symptoms, while 90-95% of total knee replacements continuing to function well more than 10 years after surgery.

Pre-operative Assessment and Exercises

Before the operation, the doctor may refer you to see a physiotherapist for a thorough assessment and/or some training sessions so as to better prepare you for the post-operative rehabilitation exercises. These help to maximize you relevant joint and muscle functions, speed up your recovery, and achieve more desirable results from the operation.

Complications

The following exercises help prevent complications such as chest infections and blood clots in your legs. You should do these every hour when you are awake immediately after the operation while resting in bed.

There is possibility of other complications associated with total knee replacement, such as nerve injury, vessel injury, superficial infection, haematoma and even loosened prosthesis. However, they are rare.

1. Breathing exercises: take five long and slow deep breaths. Each breath should be deeper than the previous breath. Think about getting the air to the very bottom of your lungs. (Repeat 5 times)
2. Circulation exercises: firmly move your ankles by pointing your feet up and down to stretch and contract your calf muscles. You may also turn each foot clockwise and counter-clockwise, keeping your toes pointed toward the ceiling. (Repeat 10 times)

Post - operation Management and Exercises

1. Advice on swelling control

After the operation, your knee will be hot and swollen, it is advisable to apply ice to your knee frequently to help to control the inflammation, pain and swelling. In addition, compression with bandages is also effective to control the swelling. Your therapist will give you relevant advices on these.

2. Walking

You will usually start walking on the first or second day after your operation. The physiotherapist will advise you on how much weight you are allowed to take on your operated leg. It is important that you practise and improve your walking before you are discharged from the hospital. The physiotherapist will advise you on what walking aids to use and how long to use them for. He/she will also advise you on how to progress your walking.

The sequence for walking is:

• Move walking aid(s) forward
• Step forward with your operated leg
• Step up to (or past) your operated leg

You can turn around in either direction but you must prevent twisting or pivoting on your new knee. You should therefore lift your feet with each step and step around with small steps. At best, you can gradually progress your walking tolerance by increasing the distance and speed, while the swelling is not increased. If the knee swells too much it is time to rest with your legs up, and/or apply some ice.

3. Advice on stairs

During your hospital stay, the physiotherapist will show you how to climb the stairs. Always use walking aids and if present a rail(s) to support and assist you while going up or down the stairs. If you do not have rails on your stairs, you should tell your therapist.

Going up

• Go up one step with your non-operated leg
• Take your operated leg up one step (along with the stick/crutches) to join the other leg

Going down

• Place your operated leg down one step beside your walking aids
• Bring your non-operated leg (along with the stick/crutches)down one step to meet the other leg

4. Transfers

Sitting down

• get close to the chair, that it touches your legs
• keep your feet apart
• slide your operated leg slightly forward
• lower yourself using your arms and legs.

Standing up

• move your bottom forward to the edge of the seat
• keep your feet apart
• slide your operated leg slightly forward
• use the armrests of the chair and push up to standing using your arms and good leg.

5. Kneeling

Kneeling is not advisable for several months following your operation, after which, you may kneel down as you feel able. But many patients find they cannot kneel after their operation either because it is uncomfortable or because they are experiencing a strange sensation.

6. Dressing

Dress sitting on a chair or the bed. It is easier to dress your operated leg first and undress it last. It is advisable to wear good supportive shoes with low heels (you may find slip-on shoes easier to manage) and to avoid tight corsets.

7. Advice on exercises

When you get home, it is very important that you continue to do all the exercises taught to you while in hospital, as advised by the physiotherapist. This is to ensure that your knee does not get stiff and to make sure that it continues to strengthen once you are home.

Exercises

The following exercises should be performed three times per day for at least 12 weeks and supervision by a physiotherapist is recommended. These exercises will help knee range and strength and should be performed pre- and post-operatively.

Heel slides on bed (knee flexion)

Bend your knee by sliding your heel up toward your buttocks while keeping your heel on the bed, then return to the starting position. Keep your kneecap pointed up toward the ceiling during the exercise. Using a plastic sheet under your heel may help it slide easier. (Repeat 10 times)

Heel slides upon sitting (knee flexion)

Sit on a chair with a towel under one foot. Slide the foot to move the heel backwards until feeling a pull in front of the knee. Hold for 20 seconds or more.

(Repeat 10 times)

Thigh squeezes (quadriceps sets)

Tighten the muscles on the front of your thigh by pushing the back of your knee down into the bed. Hold for 5 seconds and relax. (Repeat 10 times)

Straight leg raise

Tighten the muscle on the front of your thigh and pull up your toes to straighten your leg. Lift your leg a few centimetres keeping your knee straight, then lower slowly. (Repeat 10 times)

Lying kicks (small arc quads)

Have your leg slightly bent by placing a roll under your knee. Tighten your thigh muscles and straighten the knee by pulling your foot and toes up (keep your knee on the roll). Hold for 5 seconds and slowly relax. To make the exercise harder, put a small weight around your ankle.  (Repeat 10 times)

Knee straightening stretch

Sit on a chair, with the affected leg supported on a chair as shown, let our leg straighten in this position. Hold for 20 seconds or more. (Repeat 10 times)

Knee and hamstrings stretch

Sit on a chair with one leg straight in front of you. Lean forward and straighten your knee, assisting the stretch with your hands. Hold for 20 seconds or more.

(Repeat 3-5 times)

Sitting kicks (long arc quads)

Sit on a chair. Tighten your thigh muscles and straighten your knee to pull your foot and toes up. Hold for 5 seconds and slowly relax your leg. (Repeat 10 times)

Knee dangling/swinging

Sit on a bed so that your feet will not touch the floor. Allow your knees to bend. Swing your affected leg back and forth so that you feel a gently rebounding sensation. Do this for 2 to 3 minutes.

Prone knee flexion

Lie on your stomach with a towel under your thigh. Bend your knee back as far as possible. Hold for 20 seconds. (Repeat 3-5 times)

Advanced standing exercises

You may do the advanced exercises in standing position only when you are instructed by a therapist or surgeon.

Resuming normal life

You may start driving once you have spoken to the clinician in clinic, which is usually six to eight weeks after your surgery. You should be able to return to work between six and twelve weeks after the operation, but this depends on the nature of your work and how you usually get there. This is a major operation and you may tire quickly. This is normal and your strength will gradually return over the next few months.

Advice on Sports

Since the joint replacement includes a bearing surface which potentially can wear, walking or running for fitness are not recommended. Some patients feel well enough to do this and so need to exercise judgment in order to prolong the life-span of the implant materials. Swimming, water exercises, cycling, and cross country skiing (cross-trainer) can provide a high level of cardiovascular and muscular fitness without excessive wear on the prosthetic joint materials.

The above information was produced by Physiotherapy Department, Canossa Hospital (Caritas).

Please call 28255392 for physiotherapy appointment

References:

1. Royal National Orthopaedic Hosptial (NHS Trust): A Patient's Guide to Total Knee Replacement (2011). rnoh.nhs.uk
2. allinahealth.org/Health-Conditions-and-Treatments/Health-library/Patient-education/Total-Knee-Replacement/After-surgery/Knee-exercises
3. brochures.mater.org.au/brochures/mater-hospital-brisbane/total-knee-replacement